The present invention relates, generally, to product packaging, and, more particularly, to an apparatus and related method for automatically packaging food items, and especially cuts of meat, in such a manner as to automatically clean the food container before it is sealed.
There is a product line in the food industry that is generally referred to as case-ready product. Case-ready product can include meat and vegetables, as well as other food products, packaged in containers including a receptacle and a cover. The cover is preferably clear for viewing the product in the container. Often, the product is fresh and needs to be maintained in an environment that prevents contamination and premature spoilage. Case-ready product containers preferably include a plastic sheet cover substantially the same size as the receptacle opening wherein the cover is sealed to an upper portion of the receptacle. In another type of case-ready container, the cover is wrapped around the receptacle and heat shrunk to form a seal. The wrap around-type cover utilizes significantly more cover material than a cover that is substantially the same size as the opening to the receptacle. Either form of case-ready product provides a sealed environment inside the receptacle and a package that is aesthetically and functionally pleasing to the end consumer.
The interiors of case-ready containers, because they are sealed, can be flushed with various gases to help preserve the freshness of the food product to extend shelf life. Shelf life is important to both food processors, retailers and consumers in order to reduce costs and to provide safety for the end consumer.
In case ready products where the cover is heat-sealed to an upper portion of the receptacle, the use of flushing gases is particularly important because of the integrity of the seal. Machines have been designed to introduce a gas into the container while simultaneously heat sealing a durable film on the tops of lips of the receptacles that tend to be polymeric (plastic) tray-type receptacles. The machines include sealing bars that apply pressure and heat to the film creating a heat seal to secure the cover to the receptacle. When executed correctly, a pillow of gas is captured under the covering film. In cases where a good seal is not formed between the tray and cover, for example by the presence of moisture, fat and/or protein on the sealing area, a seal will not properly form and the product will have to be reworked. This adds to the cost of producing products and/or elevates the risk of premature failure of the product. Reworking requires that the tray be removed from the production line to a rework area. The cover film is removed from the tray and the tray placed into the machine for reprocessing, and typically requires a worker to remove foreign materials such as moisture, protein and/or fat from the sealing area.
Currently in the meat industry, operators manually wipe the tops of receptacles with towels. The use of operators for cleaning receptacles is expensive and sometimes results in receptacles being missed or not cleaned uniformly. In addition, when operators use towels to manually remove contaminants from the receptacles, it is up to the individual operator to determine when a towel should be disposed of and a new towel used. This can lead to sporadic quality of cleaning and can introduce the transfer of bacteria and other towel contaminants between and into receptacles.
It is also known in the food processing industry to utilize air jets to clean the tops of containers prior to sealing. This method can be successfully used with food products that tend to leave loose particulate matter or water on the sealing surface of the receptacles. However, contaminants such as proteins, fats and starches adhere more securely to the sealing surfaces. Air streams are not effective for the removal of these contaminants, to a point where sealing can be effected.
Thus, there is a need for an improved apparatus and method for cleaning the sealing surface of food receptacles that overcomes the aforementioned problems.
In one aspect of the present invention a cleaning apparatus for cleaning a portion of at least one container is disclosed. The apparatus comprises a container cleaner including a wiping material supply mechanism to support a supply of wiping material. An engaging mechanism is operable to urge the wiping material from the supply mechanism into contact with the portion of the container to be cleaned. A wiping material take-up mechanism is adapted to store the wiping material from the supply mechanism after the wiping material has contacted the containers, and a drive is operable to effect movement of the wiping material from the supply mechanism to the take-up mechanism.
Another aspect of the present invention is to provide a food packaging apparatus. The packaging apparatus comprises a conveyor operable for advancing food receptacles from a filling station to a sealing station. A container cleaner is positioned between the filling station and the sealing station, and the cleaner includes a wiping material supply mechanism to support a supply of wiping material. An engaging mechanism is operable to urge the wiping material from the supply mechanism into contact with an upper rim of each of the food receptacles passing thereunder. A wiping material take-up mechanism is adapted to store the wiping material from the supply mechanism after the wiping material has contacted the food receptacles. A drive is operable to effect movement of the wiping material from the supply mechanism to the take-up mechanism.
Yet another aspect of the present invention is to provide a method of filling and sealing food containers. The method includes placing a food product into a receptacle, the receptacle having a cover engaging surface, and advancing the filled receptacle to a cleaning station. The cover-engaging surface is then contacted with a wiping material to remove at least a portion of any contaminant present on the cover-engaging surface. The wiping material is then advanced from a supply of wiping material to a take-up mechanism and a cover is adhered to the receptacle at the cover-engaging surface.